Visible light communication (VLC) signal monitoring method, device, equipment and storage medium

Abstract

The application provides a visible light communication (VLC) signal monitoring method, device and equipment and a storage medium. The VLC signal monitoring method comprises the following steps: constructing a VLC communication system in a network; arranging a plurality of LED light sources and photodetectors with encoders in an LED coverage area; the plurality of LED light sources carry coded light signals and transmit the light signals to the photodetectors through free space; the photodetectors calculate current light flux and current received power after receiving the light signals; and the calculated current light flux and current received power are compared with light flux initial threshold and received power initial threshold set by historical analysis data to determine whether the current received light signal state is normal. The application uses a spatial integral method to calculate the light flux and set the light flux initial threshold by historical analysis data to measure whether the input light signal state is normal, and provides data reference for optimizing the transmission power of the same service type radio wave of the transmitting end.

Description

Technical Field

[0001] This invention relates to the field of visible light communication, and more particularly to a method, apparatus, device, and storage medium for monitoring visible light communication (VLC) signals. Background Technology

[0002] 6G networks, by integrating non-terrestrial communication (NTN) into terrestrial cellular systems, can achieve true global coverage, maintaining high availability and robustness even in the event of natural disasters. The integrated terrestrial and NTN networks facilitate the expansion of cellular network coverage through NTN nodes, ensuring users can access the network anytime, anywhere, and providing mobile broadband service to areas with no or insufficient service, bridging coverage gaps in areas such as oceans, mountains, forests, or other remote areas where it is difficult to deploy terrestrial access points or base stations. Besides enhancing services, integrated terrestrial and NTN networks can also bring many new services and applications, including ubiquitous connectivity, remote sensing, passive sensing and positioning, navigation, tracking, and autonomous delivery. In 6G, the implementation of UM-MIMO communication requires prior research and development of channel models to understand the impact on plasma trains and the propagation of numerous parallel waves in space. Terahertz systems may be applied in the convergence of future 6G wireless communication networks. As the frequency range used in 6G mobile communication systems continues to expand, the frequency loss varies considerably. In particular, compared to the loss below 6GHz, the loss in the terahertz high-frequency band is significantly increased. Therefore, the propagation attenuation loss characteristics of 6G frequency band applications need to be considered and analyzed.

[0003] Visible Light Communications (VLC) is a wireless communication technology that uses the flickering signals emitted by objects such as fluorescent lamps or light-emitting diodes (LEDs) to transmit information. Visible light has a frequency between 400 THz (wavelength 780 nm) and 800 THz (wavelength 375 nm). When using ordinary fluorescent lamps, its transmission rate is 10 kbit / s. When using LED lamps, it can reach 500 Mbit / s.

[0004] Effective signal monitoring and processing of received optical signals is required to complete the health assessment of the entire lifecycle of the VLC communication system through a combination of optical flux indicators and received power, and to provide data reference for optimizing the transmission power of radio waves of the same service type at the transmitting end. These issues urgently need to be addressed. Summary of the Invention

[0005] Purpose of the invention: To propose a method, apparatus, device, and storage medium for monitoring visible light communication (VLC) signals, in order to solve the aforementioned problems existing in the prior art.

[0006] Firstly, a method for monitoring visible light communication (VLC) signals is proposed, with the following steps:

[0007] A VLC communication system is constructed within the network; the VLC communication system includes a predetermined range of LED coverage area, within which several LED light sources with encoders and photodetectors are arranged;

[0008] Several LED light sources carry encoded light signals and transmit the light signals to the photodetector through free space;

[0009] After receiving the optical signal, the photodetector calculates the current optical flux and the current received power.

[0010] The calculated current optical flux and current received power are compared with the initial thresholds for optical flux and received power set in the historical analysis data to determine whether the current received optical signal is normal.

[0011] In a further embodiment of the first aspect, calculating the current luminous flux includes: calculating the current luminous flux F using spatial integration. T The expression for the spatial integration method is as follows:

[0012]

[0013] In the formula, I0 represents the axial intensity, i.e., the luminous intensity at a solid angle of 0°; θ max The half-beam angle is the angle at which the light intensity decreases to half of its axial intensity; g t (θ) represents the brightness of the LED at angle θ, and the unit is Candela.

[0014] In a further embodiment of the first aspect, after receiving the optical signal, the photodetector calculates the received power by constructing a collision model and a migration model for the data set of transmitted optical signals that are lower than the initial threshold of optical flux.

[0015] If the calculated result is less than 50% of the optical signal power of the transmitting unit, the received optical signal is deemed to have failed to be received.

[0016] In a further embodiment of the first aspect, after determining that the received optical signal has failed to be received:

[0017] In the VLC communication system, collision detection is used to find other optical receiving nodes and the received power is calculated to confirm whether it is a false alarm at the receiving end; then, the system is migrated to the clutter node and retained for a period of time before being cleared.

[0018] At the same time, the VLC receiver transmits commands requiring the transmitter to retransmit or increase the transmission power.

[0019] In a further embodiment of the first aspect, the collision model expresses, at a predetermined time and a predetermined spatial point, obtaining the correction amount of the velocity probability distribution in each direction at that spatial point based on the equilibrium state function at that time and place.

[0020] The collision model expression is as follows:

[0021]

[0022] In the formula, f i (x,t) represents the probability density function at time t; f i (x, t+Δt) represents the probability density function at time t+Δt; Let represent the equilibrium distribution function at time t; This represents the relaxation factor.

[0023] In a further embodiment of the first aspect, the migration model expresses, at a predetermined time and a predetermined spatial point, the probability density function of the collision at the spatial point is transferred to the corresponding position of the adjacent grid node, and the value at that position is replaced; at the same time, the spatial point also receives values ​​transferred from other adjacent grid nodes and replaces the corresponding local values.

[0024] In a further embodiment of the first aspect, the migration model expression is as follows:

[0025] f i (x+e i ·Δt,t)=f i (x,t)

[0026] In the formula, e i f represents the migration factor; i (x+e i ·Δt,t) represents e i The probability density function at time Δt; f i (x,t) represents the probability density function at time t.

[0027] In a further embodiment of the first aspect, the current received power is calculated using path loss and spectral power distribution. The calculation formula is as follows:

[0028]

[0029] In the formula, S R (λ) represents the spectral power distribution; R f (λ) represents the spectral response of the filter; λ λ Indicates the lower wavelength cutoff value of the filter; λ dt This indicates the higher wavelength cutoff value of the filter;

[0030] Among them, S R (λ)=L L S T (λ); L L S represents path loss; T (λ) represents the spectral power distribution.

[0031] In a further embodiment of the first aspect, when there are N LEDs in a lamp, the photodetector simultaneously receives signals from multiple LEDs, and the total received power is the sum of the received power of the N LEDs. At this time, the total received power P of the LOS channel is... R (total) is represented as:

[0032]

[0033] In the formula, N represents the number of LEDs; P r (i) represents the current actual received power of the i-th LED.

[0034] In a further embodiment of the first aspect, the method for determining the initial threshold of luminous flux includes:

[0035] Obtain the most recent 10, 100, and 1000 light flux data from the logs as historical light flux data; calculate the weighted average of the historical light flux data to obtain the light flux threshold average line;

[0036] Using all historical luminous flux data as the denominator and the number of times the luminous flux threshold average line was exceeded in the historical luminous flux data as the numerator, the proportion of luminous flux anomalies to the most recent 10, 100, and 1000 times was obtained, which was used as the predicted value of luminous flux anomalies for the next LED.

[0037] If the difference between the 10, 100, and 1000 luminous flux predictions is within 10%, the weighted average is used to obtain the final luminous flux prediction value; if the difference is greater than 10%, the short-term luminous flux prediction value of the 10th time is used.

[0038] A second aspect of the present invention provides a visible light communication (VLC) signal monitoring device, comprising an LED coverage area, an LED light source, and a photodetector. The LED light source and the photodetector are respectively arranged within the LED coverage area; several LED light sources carry encoded optical signals and transmit the optical signals to the photodetector through free space. The photodetector has a built-in first calculation module and a comparison module. When the photodetector receives an optical signal, the first calculation module calculates the current luminous flux and the current received power. The comparison module compares the calculated current luminous flux and the current received power with initial threshold values ​​for luminous flux and received power set from historical analysis data to determine whether the currently received optical signal is normal.

[0039] In a further embodiment of the second aspect, the first calculation module is further configured to construct a collision model and a migration model after the photodetector receives the optical signal, and to calculate the received power in combination with the data set of transmitted optical signals that are lower than the initial threshold of optical flux; if the calculation result is lower than 50% of the optical signal power of the transmitting unit, it is determined that the received optical signal is a reception failure.

[0040] In a further embodiment of the second aspect, the signal monitoring device further includes a judgment module; the judgment module is used to find other optical signal receiving nodes in the VLC communication system by collision and calculate the receiving power to confirm whether it is a false alarm at the receiving end; then, it is migrated to the clutter node by migration model, retained for a period of time, and then cleared; at the same time, the VLC receiver stage sends a command to require the transmitting end to retransmit or increase the transmission power.

[0041] A third aspect of the present invention provides an electronic device comprising a processor and a memory storing computer program instructions; wherein the processor, when executing the computer program instructions, implements the visible light communication (VLC) signal monitoring method as described in the first aspect and its further embodiments.

[0042] A fourth aspect of the present invention provides a computer-readable storage medium, characterized in that the storage medium stores at least one executable instruction, which, when executed on an electronic device, causes the electronic device to perform the visible light communication (VLC) signal monitoring method as described in the first aspect and its further embodiments.

[0043] Beneficial Effects: The Visible Light Communication (VLC) signal monitoring method proposed in this application innovatively constructs a VLC communication system within a large or ultra-large network. Indoors, optical signals carrying data are transmitted through the area covered by LED lights. These signals travel through free space to a photodetector at the receiving end. After receiving the optical signal, the photodetector converts it into an electrical signal, which is then post-equalized, demodulated, and decoded to recover the original transmitted signal. Innovatively, at the LED stage, based on the available parameters of the LED transmitter, the method uses spatial integration to calculate the luminous flux and historical analysis data to set an initial threshold for the luminous flux, thereby measuring the normality of the input optical signal. This allows the VLC communication system to comprehensively evaluate the health of the entire lifecycle of the optical signal to wireless signal conversion process by combining luminous flux indicators with received power. It also provides data reference for optimizing the transmission power of radio waves of the same service type at the transmitting end. Attached Figure Description

[0044] Figure 1 This is a flowchart of the VLC signal monitoring method in an embodiment of the present invention.

[0045] Figure 2 This is a probability density direction and probability density distribution diagram in an embodiment of the present invention.

[0046] Figure 3 This is a schematic diagram of a visible light communication (VLC) signal monitoring device in an embodiment of the present invention. Detailed Implementation

[0047] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0048] This embodiment discloses a method for monitoring visible light communication (VLC) signals. Figure 1 In large or ultra-large network deployments, VLC communication systems are constructed. Indoors, optical signals carrying data are transmitted through LED lights within a covered area. These signals travel through free space to a photodetector at the receiving end. Upon receiving the optical signal, the photodetector converts it into an electrical signal, which is then post-equalized, demodulated, and decoded to reconstruct the original transmitted signal. Innovatively, at the LED stage, based on the available parameters of the LED transmitter, a spatial integration method is used to calculate the luminous flux, and historical analysis data is used to set an initial threshold for the luminous flux to assess the normality of the input optical signal.

[0049] Specifically, the luminous flux is calculated using the spatial integration method based on the available parameters of the given LED emitter.

[0050] Utilizing the spatial emission characteristics of LEDs. Using luminous intensity g t (θ) Measures the luminance of an LED in a specific direction. Measurements are taken in Candela, which is the luminous flux per unit solid angle. Luminous intensity includes two important parameters: axial intensity, defined as the luminous intensity at a 0° solid angle, and half-beam angle θ. max This is the angle at which the light intensity decreases to half of its axial intensity. The luminous flux is calculated using spatial integration:

[0051]

[0052] The process of setting the initial threshold for luminous flux is as follows:

[0053] First, retrieve historical luminous flux data from the logs, specifically the most recent 10, 100, and 1000 times. Then, calculate a weighted average of all historical luminous flux data to obtain the luminous flux threshold average.

[0054] Secondly, the number of times the luminous flux threshold was exceeded by the average number of times the data from the most recent 10, 100, and 1000 times was counted as the denominator and the number of times the luminous flux was exceeded by the average number of times the data exceeded the threshold was counted as the number of anomalies. The proportion of luminous flux anomalies to the most recent 10, 100, and 1000 times was used as the predicted value of luminous flux anomalies for the next time the LED passes through it.

[0055] Then, the differences between the three luminous flux prediction values ​​(10, 100, and 1000 times) are compared. If the differences are within 10%, a weighted average is taken to obtain the final luminous flux prediction value. If the difference is greater than 10%, the short-term luminous flux prediction value (10 times) is used.

[0056] Collision and migration are two core steps in LBM (Light Filtering Model). Since a higher light flux indicates stronger light emission from the emitter, the VLC (Vibration Logic Controller) communication system innovatively constructs a collision and migration model to calculate the received power for data sets where the transmitted optical signal is below the initial light flux threshold. If the calculated result is below 50% of the transmitter's optical signal power, it is considered a reception failure. Within the VLC, collisions are used to find other optical signal receiving nodes, and the received power is calculated to confirm whether it is a false alarm at the receiver. Then, the migration model is used to migrate the signal to a cluttered node, retain it for a period of time, and then clear it. Simultaneously, the VLC receiver sends a command to the transmitter to retransmit or increase the transmission power. This allows the VLC communication system to comprehensively evaluate the health of the entire lifecycle of the optical signal to wireless signal conversion process by combining light flux indicators with received power. It also provides data reference for optimizing the transmission power of radio waves of the same service type at the transmitter.

[0057] Received power calculation:

[0058] The received power is calculated using path loss, photometric function, and spectral power, using the following formula:

[0059]

[0060] In the formula, S R (λ) represents the spectral power distribution; R f (λ) represents the spectral response of the filter; λ λ Indicates the lower wavelength cutoff value of the filter; λ dt This indicates the higher wavelength cutoff value of the filter.

[0061] When a lamp contains N LEDs, the photodetector can simultaneously receive signals from multiple LEDs. The total received power is the sum of the received power from all N LEDs. In this case, the LOS channel received power is expressed as:

[0062]

[0063] The collision model is constructed as follows:

[0064] This refers to the evolution of the probability density function of a node over time. Specifically, it can be described as follows: at a given moment and spatial point, based on the equilibrium function at that time and place, the correction amount of the velocity probability distribution in each direction at that point is obtained, thus realizing the evolution of the probability density function at that point. For a single-relaxation model, the collision term is controlled by only one relaxation factor, as shown in the following formula:

[0065]

[0066] In the formula, f i (x,t) represents the probability density function at time t; f i (x, t+Δt) represents the probability density function at time t+Δt; Let represent the equilibrium distribution function at time t; This represents the relaxation factor.

[0067] here The value of has a certain range, in principle This is the required range for LBM simulation of incompressible fluids; neglecting this may lead to incorrect calculation results.

[0068] Migration is the spatial evolution of a flow field. Its function is to, at a given moment and spatial point, transfer the probability density function of that point through collisions to the corresponding positions of neighboring grid nodes, replacing the values ​​at those positions. Simultaneously, the point also receives values ​​transferred from other neighboring grid nodes, replacing their corresponding local values. After all values ​​have been migrated and replaced, the flow field's density, velocity, etc., can be updated, thus realizing the spatial evolution of the flow field. The migration formula is:

[0069] f i (x+e i ·Δt,t)=f i (x,t)

[0070] The following discloses an implementation process for the migration of this patent:

[0071] See Figure 2 As shown, the velocity distribution in the 9th direction (at the center point) remains unchanged during the migration. Therefore, when implementing the migration steps, only the changes in the velocity distribution in the 8 directions are considered. Assuming the grid point at position "9" in the diagram has coordinates (i,j), consider which node f should migrate to and which node it should migrate to. Clearly, f should migrate one grid to the right, so it needs to be assigned to point (i+1,j); f should migrate to the upper right, i.e., it needs to migrate to point (i+1,j+1). Migration in other directions follows similar steps. Therefore, from the perspective of the migration implementation process, its essence is an array "shifting" operation. In the program implementation, the shifting operation can be performed using a loop, or it can be implemented by manipulating the addresses of array elements. For the latter, the corresponding MATLAB code is as follows:

[0072] 1 function F1=stream(F1, 1x, 1y)

[0073] 2 F1(:,:,4)=F1([2:1x1],[1y1:1y-1],4);

[0074] 3 F1(:,:,3)=F1(:,[1y1:1y-1],3);

[0075] 4 F1(:,:,2)=F1([1×1:1x-1],[1y1:1y-1],2);

[0076] 5 F1(:,:,5)=F1([2:1×1],:,5);

[0077] 6 F1(:,:,1)=F1([1×1:1x-1],:,1);

[0078] 7 F1(:,:,6)=F1([2:1×1],[2:1y1],6);

[0079] 8 F1(:,:,7)=Ω(:,[2:1y1],7);

[0080] 9 F1(:,,8)=F1([1×1:1x-1],[2:1y1],8);

[0081] Taking the second line of code "F1(:,:,4)=F1([2:lx 1],[ly 1:ly-1],4)" as an example, from Figure 2 As we can see, the fourth direction is the upper left direction, and the value in this direction needs to be obtained by migrating from the fourth direction of point (i+1, i-1). The left side of the equals sign in the code represents the node receiving the migration, and the right side represents the node sending the migration value. It's also worth noting that both the left and right sides of the equals sign operate on the array F1, but this does not affect the modification of its local element values.

[0082] Indoors, light signals carrying data are transmitted through the area covered by LED lights. The light signals are transmitted through free space to the photodetector at the receiving end. After receiving the light signals, the photodetector converts the signals into electrical signals and performs post-equalization, demodulation, and decoding to restore the original transmitted signals.

[0083] As a preferred embodiment, a visible light communication (VLC) signal monitoring device is also proposed, see [link to documentation]. Figure 3 As shown, the signal monitoring device includes an LED coverage area, LED light sources, and a photodetector. The LED light sources and photodetector are arranged within the LED coverage area; several LED light sources carry encoded light signals and transmit the light signals to the photodetector through free space. The photodetector has a built-in first calculation module and a comparison module. When the photodetector receives a light signal, the first calculation module calculates the current luminous flux and the current received power. The comparison module compares the calculated current luminous flux and the current received power with the initial threshold values ​​for luminous flux and received power set by historical analysis data to determine whether the currently received light signal is normal. The first calculation module is further used to construct a collision model and a migration model after the photodetector receives the light signal, and to calculate the received power for data sets where the transmitted light signal is lower than the initial threshold value; if the calculation result is lower than 50% of the light signal power of the transmitting unit, the received light signal is determined to be a reception failure. The signal monitoring device also includes a judgment module; the judgment module is used to find other optical signal receiving nodes in the VLC communication system by collision and calculate the receiving power to confirm whether it is a false alarm at the receiving end; then it is migrated to the clutter node by migration model, retained for a period of time and then cleared; at the same time, the VLC receiver link sends a command to require the transmitter to retransmit or increase the transmission power.

[0084] As a preferred embodiment, an electronic device is also proposed, comprising a processor, a memory, a communication interface, and a communication bus. The processor, memory, and communication interface communicate with each other via the communication bus. The memory stores at least one executable instruction that causes the processor to execute the visible light communication (VLC) signal monitoring method disclosed in the above embodiments. The electronic device can also communicate with one or more external devices (e.g., keyboards, pointing devices, Bluetooth devices, etc.), one or more devices that enable users to interact with the electronic device, and / or any device that enables the electronic device to communicate with one or more other computing devices (e.g., routers, modems, etc.). This communication can be performed via an input / output (I / O) interface. Furthermore, the electronic device can also communicate with one or more networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks, such as the Internet) via a network adapter. The network adapter communicates with other modules of the electronic device via a bus. It should be understood that other hardware and / or software modules can be used in conjunction with the electronic device, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0085] As a preferred embodiment, a computer-readable storage medium is provided, storing at least one executable instruction that, when executed on an electronic device, causes the electronic device to perform the path detection method for IPv6 segmented routing as described in the above embodiments. More specific examples of the computer-readable storage medium in this disclosure may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. The computer-readable storage medium may include a data signal propagated in baseband or as part of a carrier wave, carrying readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The readable signal medium may also be any readable medium other than a readable storage medium, which can send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0086] In summary, the VLC communication system disclosed in this application is constructed within a large or ultra-large network. Indoors, optical signals carrying data are transmitted through LED lights within a covered area. These signals are then transmitted in free space to a photodetector at the receiving end. Upon receiving the optical signal, the photodetector converts it into an electrical signal, performs post-equalization, demodulation, and decoding to reconstruct the original transmitted signal. Innovatively, at the LED stage, based on the available parameters of the LED transmitter, the luminous flux is calculated using a spatial integration method, and an initial threshold for luminous flux is set using historical analysis data to assess the normality of the input optical signal.

[0087] Collision and migration are two core steps in LBM (Light Filtering Model). Since a higher light flux indicates stronger light emission, the VLC (Vibration Logic Controller) communication system innovatively constructs a collision and migration model to calculate the received power for data sets where the transmitted optical signal is below the initial light flux threshold. If the calculated result is below 50% of the transmitter's optical signal power, it is considered a reception failure. Within the VLC, collisions are used to find other optical signal receiving nodes, and the received power is calculated to confirm whether it is a false alarm. After confirming the reception failure, the system is migrated to a clutter node using the migration model, where it remains for a period before being cleared. Simultaneously, the VLC receiver sends a command to the transmitter to retransmit or increase the transmission power. This allows the VLC communication system to comprehensively evaluate the health of the entire lifecycle of the optical signal to wireless signal conversion process by combining light flux indicators with received power. It also provides data reference for optimizing the transmission power of radio waves of the same service type at the transmitter.

[0088] As described above, although the invention has been shown and described with reference to specific preferred embodiments, it should not be construed as limiting the invention itself. Various changes in form and detail may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method for monitoring visible light communication (VLC) signals, characterized in that, include: A VLC communication system is constructed within the network; the VLC communication system includes a predetermined range of LED coverage area, within which several LED light sources with encoders and photodetectors are arranged; Several LED light sources carry encoded light signals and transmit the light signals to the photodetector through free space; After receiving the optical signal, the photodetector calculates the current optical flux and the current received power. By constructing a collision model and a migration model, it calculates the received power for data sets where the transmitted optical signal is lower than the initial threshold of optical flux. If the calculation result is lower than 50% of the optical signal power of the transmitting unit, it is determined that the received optical signal has failed. The collision model expresses the correction amount of the velocity probability distribution in each direction at a predetermined time and a predetermined spatial point, based on the equilibrium state function at that time and place. The collision model expression is as follows: In the formula, Let represent the probability density function at time t; express The probability density function at time t; Let represent the equilibrium distribution function at time t; Indicates the relaxation factor; The calculated current optical flux and current received power are compared with the initial thresholds for optical flux and received power set in the historical analysis data to determine whether the current received optical signal is normal.

2. The VLC signal monitoring method according to claim 1, characterized in that, The calculation of the current luminous flux includes: calculating the current luminous flux using the spatial integration method. The expression for the spatial integration method is as follows: In the formula, This represents the axial intensity, i.e., the luminous intensity at a solid angle of 0°. The half-beam angle is the angle at which the light intensity decreases to half of its axial intensity. Indicates LED in Brightness at an angle, measured in Candela.

3. The VLC signal monitoring method according to claim 1, characterized in that, After determining that the received optical signal has failed: In the VLC communication system, collision detection is used to find other optical receiving nodes and the received power is calculated to confirm whether it is a false alarm at the receiving end; then, the system is migrated to the clutter node and retained for a period of time before being cleared. At the same time, the VLC receiver transmits commands requiring the transmitter to retransmit or increase the transmission power.

4. The VLC signal monitoring method according to claim 1, characterized in that, The migration model expresses that at a predetermined time and a predetermined spatial point, the probability density function of the spatial point after collision is transferred to the corresponding position of the adjacent grid node, and the value at that position is replaced; at the same time, the spatial point also receives values ​​transferred from other adjacent grid nodes and replaces the corresponding local values.

5. The VLC signal monitoring method according to claim 1, characterized in that, The migration model expression is as follows: In the formula, Indicates migration factor; express The probability density function at time t; Let represent the probability density function at time t.

6. The VLC signal monitoring method according to claim 1, characterized in that, Calculate the current received power using path loss and spectral power distribution. The calculation formula is as follows: In the formula, Indicates the spectral power distribution; Indicates the spectral response of the filter; This indicates the lower wavelength cutoff value of the filter; This indicates the higher wavelength cutoff value of the filter; in, ; Indicates path loss; This represents the spectral power distribution.

7. The VLC signal monitoring method according to claim 1, characterized in that, When a lamp contains N LEDs, the photodetector receives signals from multiple LEDs simultaneously. The total received power is the sum of the received power from all N LEDs. At this time, the total received power of the LOS channel is... Represented as: In the formula, N represents the number of LEDs; This represents the current actual received power of the i-th LED.

8. A visible light communication (VLC) signal monitoring device, characterized in that, include: The LED coverage area within the predetermined range; LED light sources and photodetectors are respectively arranged within the LED coverage area; Several LED light sources carry encoded light signals and transmit the light signals to the photodetector through free space; The first computing module is built into the photodetector; When the photodetector receives an optical signal, the first calculation module calculates the current optical flux and the current received power. By constructing a collision model and a migration model, the data set of transmitted optical signals that are lower than the initial threshold of optical flux is combined with the received power for calculation. If the calculation result is lower than 50% of the optical signal power of the transmitting unit, it is determined that the reception of this optical signal has failed. The collision model expresses the correction amount of the velocity probability distribution in each direction at a predetermined time and a predetermined spatial point, based on the equilibrium state function at that time and place. The collision model expression is as follows: In the formula, Let represent the probability density function at time t; express The probability density function at time t; Let represent the equilibrium distribution function at time t; Indicates the relaxation factor; The comparison module is built into the photodetector; the comparison module compares the calculated current light flux and current received power with the initial threshold of light flux and initial threshold of received power set in the historical analysis data to determine whether the current received light signal is normal.

9. The visible light communication (VLC) signal monitoring device according to claim 8, characterized in that, The first calculation module is used to construct a collision model and a migration model after the photodetector receives the light signal, and to calculate the received power in combination with the data set of light signals that are lower than the initial threshold of light flux. If the calculation result is lower than 50% of the light signal power of the transmitting unit, it is determined that the received light signal has failed.

10. The visible light communication (VLC) signal monitoring device according to claim 9, characterized in that, It also includes a judgment module; the judgment module is used to find other optical signal receiving nodes in the VLC communication system by collision and calculate the received power to confirm whether it is a false alarm at the receiving end; Then, the debris node is migrated to the migration model and retained for a period of time before being cleared; at the same time, the VLC receiver stage sends a command to the transmitter to retransmit or increase the transmission power.

11. An electronic device, characterized in that, The device includes: a processor and a memory storing computer program instructions; the processor executes the computer program instructions to implement the visible light communication (VLC) signal monitoring method as described in any one of claims 1 to 7.

12. A computer-readable storage medium, characterized in that, The storage medium stores at least one executable instruction, which, when executed on an electronic device, causes the electronic device to perform the visible light communication (VLC) signal monitoring method as described in any one of claims 1 to 7.

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